One of the methods used today to protect petroleum or gas pipelines from corrosion is to wrap corrosion-resistant tape around base steel pipes in the field. The support of the corrosion-resistant tape is usually made of a polyethylene film or sheet that is economical and exhibits good low temperature performance and high chemical stability. The adhesive layer on the tape is usually made of butyl rubbers having low water permeabilties.
The conventional corrosion-resistant tape is usually available in a roll form, without release paper attached to the tape, because of economy and the ease with which the corrosion-resistant tape can be wrapped around steel pipes. However, in wrapping operations in cold climates (e.g., about -30.degree. C.), the adhesive layer may detach from the support while the corrosion-resistant tape being unrolled.
The polyethylene film or sheet is usually surface-treated by the chromate comnversion process or corona discharge in order to provide better adhesion to the adhesive layer. However, even this method does not ensure complete prevention of the detachment of the adhesive layer from the support at cryogenic temperatures (i.e., about -30.degree. C.), particularly when the corrosion-resistant tape is unrolling at fast speed for mechanical wrapping around the steel pipe. In order to avoid this problem, the corrosion-resistant tape must be kept in a warming chamber and taken out just before use in cold climates, but this greatly reduces the efficiency of wrapping operations.